The invention relates to a welding wire conveyor device.
A multitude of welding wire conveyor devices for conveying welding wire to a welding torch are known from the prior art. The welding wire conveyor device is arranged between a welding wire receptacle and the welding torch and is preferably used if the welding wire is to be conveyed across particularly large distances, as is the case in shipbuilding, bridge engineering and hall construction, for example. In this context, the welding wire is supplied by a cable assembly package to the welding wire conveyor device and thereafter to the welding torch.
DE 10 2005 041 695 B4 describes a welding wire conveyor device which has a drive roll and a pivotable counter-pressure roll. A lever is actuated in order to pivot the counter-pressure roll in a direction away from the drive roll receiver. The lever is coupled to a spring such that the counter-pressure roll is pivoted immediately in a direction toward the drive roll receiver, as soon as the lever is no longer actuated.
The disadvantage of this embodiment is that it requires at least two persons to insert the welding wire into the welding wire conveyor device. Inserting the welding wire in this way may become necessary, if the welding wire breaks loose during operation, or if a new welding wire is needed for welding. To insert the welding wire into the welding wire conveyor device it is necessary that the user actuates the lever in order to move the counter-pressure roll away from the drive roll. Without actuating the lever there is the risk that the welding wire buckles during the insertion into the welding wire conveyor device, because of the small space between the counter-pressure roll and the drive roll. This means that the first user must actuate the lever during the entire insertion process to prevent the welding wire from buckling. When actuating the lever, the user must guide the welding wire such that the welding wire does not bypass the drive roll but instead is moved between the drive roll and the counter-pressure roll.
Since the user needs one hand for actuating the lever and must use the other hand to guide the welding wire between the drive roll and the counter-pressure roll, another person is required to operate a current source device. The current source device must be operated, since it facilitates advancing a de-energized welding wire into the welding wire conveyor device.
US 2006/0 278 624 A1 discloses a welding wire conveyor device with two roll receivers on which two rolls are arranged. The first roll is coupled to a pivoted lever. When the pivoted lever is pivoted from a first position into a second position, an abutment section of the pivoted lever strikes against a protruding section of a bearing section, on which the first roll is supported. By the pushing the pivoted lever against the protruding section, the first roll will be pivoted about a fulcrum. After the first roll has been pivoted, it will be locked in this pivoted position. The pivoted lever is moved translatory for this purpose.
Furthermore, GB 301 125 A discloses a welding wire conveyor device with two conveyor rolls arranged on separate roll receivers, wherein one of the roll receivers can be pivoted from a first position into a second position against the force of a spring by means of a multiple-part lever mechanism. In order to lock the roll receiver in the second position, a second lever mechanism with a latch hook is provided, which can be engaged with a corresponding latch recess on a part of the first lever mechanism. A spring is moreover provided on the second lever mechanism, which automatically closes the latch connection when pivoting the roll receiver into the second position. On the other hand, to pivot the roll receiver back into the first position, it is necessary to first disconnect the latch connection manually by actuating the second lever mechanism. Such type of a locking device with two, in particular multiple-part lever mechanisms, is very complex in terms of engineering, however, and is therefore cost-intensive and moreover complicated to handle.